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Serial garbage using ATmega8, STK500, CodeVisionAVR

Hi All,

I'm new to the ATmega8 and I'm trying to do some serial communication, but all I get out is garbage!? (look bottom).

I use STK500 and CodevisionAVR. Using code wisard generates this.

// USART initialization // Communication Parameters: 8 Data, 1 Stop, No Parity // USART Receiver: On // USART Transmitter: On // USART Mode: Asynchronous // USART Baud rate: 19200 UCSRA=0x00; UCSRB=0xD8; UCSRC=0x86; UBRRH=0x00; UBRRL=0x19;

And acording to the datasheet, that looks correct. But as you can see below, what I get back I can't decode?!? There are to many data and many are equal? I just do not get it.! What have I forgotten, what is it I have missed?

Hope some one can help me with this problem..!

Henning

Program cut:

for(g=0;g

Reply to
Henning M
Loading thread data ...

What crystal are you using? The baudrate depends on this...

SFC

"Henning M" schreef in bericht news:aba91$43f0d6c4$3e3d8433$ snipped-for-privacy@news.arrownet.dk...

Reply to
SFC

The crystal is a 8.000Mhz

I tried all speeds down to 600 baud with the asme result.. :(

Something else is going wrong!?

Henning

Reply to
Henning M

I don't see any code here that actually writes the character to the usart register.

Please post the WHOLE loop.

Reply to
noone

Are the fuse bits set to run from external crystal? By default I think the chip runs on internal oscillator.

Tom

Reply to
Tom

[snip...snip...]

Setting the fuse to run from an external crystal instead of the (default) internal RC oscillator.

It *is* documented but it is also easy to miss if you don't know to look for it. Would be handy if Atmel included a "boilerplate setup" section that collected all the notes like this, probably somewhere around the section where they detail the typical interrupt vector table.

--
Rich Webb   Norfolk, VA
Reply to
Rich Webb

I have now set up the fuses to run from the external crystal, and found out that a jumper (oscsel) on the STK500 was set up to use the omboard clock generator instead of the crystal. Well it only took 4-5 days to figure out :/

Thanks alot for everybodys help :)

Henning

---- It WORKS----

Reply to
Henning M

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